Compatible with all 20mm ball mount base60MM to 40MMWXRYLYN mounting arm features 60mm -40mm Locking Adjustable Carbon Fiber Kevlar Mounting Arm with Articulating Joint Dual 20mm Socket EndsThe extension arm is made of carbon fiber, while the clamps at the front and rear ends are made of aluminum alloyEXPANDS OPEN FROM 15mm UP TO 23 mm( 5.91 inches- 9.06 inches), fit a wide variety of tablets and is compatible with most Apple iPads & Android tablets without a case. For use in landscape mode only. Also compatible with Samsung Z Fold phoneOn the back side of the tablet holder is an integrated 20mm ( 0.787 inches) ball base which attaches seamlessly to the included Carbon Fiber Kevlar Mounting Arm